Although conventionally, as a reflection base for photography, so-called baryta paper, made of paper whose one surface is coated with a baryta layer composed mainly of barium sulfate, is used, recently use has been made of a waterproof base obtained by both-side coating of base paper with a resin, so that development processing may be simplified and may be made rapid. However, even if such a waterproof base is used, penetration of developing solutions from the cut end of the base cannot be prevented. The developing solution penetration from the cut surfaces of the ends cannot be eliminated by a short-period treatment, and the penetrated part turns brown due to heat or with time, which becomes stain at the edge sections of the photograph, thereby spoiling considerably the photographic value. To prevent such edge stain, a technique wherein base paper layers are made highly sized is attempted.
For example, aliphatic acid soap-type sizing agents, as shown in JP-B ("JP-B" means examined Japanese patent publication) No. 26961/1972, and alkylketene dimers, as shown in JP-A ("JP-A" means unexamined published Japanese patent application) No. 132822/1986, are used as sizing agents for photographic base paper, but they have their respective disadvantages and are not satisfactory. That is, aliphatic acid soap-type sizing agents have such defects as that the sizing effect is low against the alkalis in developing solutions, the strength of the paper decreases greatly as the added amount of the sizing agent is increased, and the stiffness of the paper lowers. On the other hand, in the case of alkylketene dimers, although the sizing property against water is good, they have such defects as that the sized properties against alkaline water and water containing organic solvents, such as alcohols, are poor, and known polyamide-polyamine-epichlorohydrin resin as a fixing agent is required to be used in a relatively large amount. Thus, neither sizing agent is satisfactory enough to be used for photographic base paper.
That is, it is strongly desired to develop such a technique that edge stain is prevented by using smaller amount of sizing agent, in view of paper strength and stiffness, in combination with a smaller amount of polyamide-polyamine-epichlorohydrin resin.
In recent years, in the photographic processing of color photographic materials, along with the shortening of the delivery period of the finished product and the lightening of the laboratory work, desirably the processing time is shortened and the replenishing amount of the processing solution and the amount of waste liquor are reduced. These are already effected practically in mini-laboratories and is spreading into the market. Along with the rapid processing, processing conditions, for example, the increase of the processing solution temperature, the shortening of the washing out period, the deterioration (coloring and tar-forming for the developing solution) of the processing solution owing to the reduction of the replenishing amount, and the increase of the accumulated concentration of materials dissolved out from the photographic material are becoming severe, and it is earnestly desired to find a solution to the above edge stain problem.